Muskmelon (Cucumis melo L.) is cultivated for the nutritional and medicinal values. Information on nutrient requirements which is important components of improved cultural practices for production. A field experiment was conducted at the Teaching and Research Farm of Ekiti State University, Ado-Ekiti, Nigeria in the rainy seasons of 2017 and 2018. This study aims to evaluate the growth and yield responses of muskmelon to varying rates of NPK 15-15-15 fertilizer rates (0, 167, 333 and 500 kg ha-1) in a randomized complete block design. Data were collected on growth parameters, number and weight of fruits. The data were subjected to analysis of variance and treatment means separated with Duncan's multiple range test. NPK fertilizer rates increased vegetative growth and fruit yield linearly. Muskmelon's response to varying rates of NPK 15-15-15 followed the same trend in the two seasons, and fertilizer application reduced day to flowering significantly. The 500 kg ha-1 NPK 15-15-15 fertilizer produced a significantly higher number of fruits ha-1, but 333 kg ha-1 NPK 15-15-15 fertilizer produced higher quality fruits culminating in higher fruit yield (17.3 t ha-1) and therefore recommended.